Electrolyte Management Guide

Comprehensive management of sodium and potassium disorders following latest clinical guidelines and evidence-based protocols.

Updated 2024 Evidence-Based Critical Care

Quick Electrolyte Assessment & Management Plan

Sodium Level (mEq/L)

Potassium Level (mEq/L)

135-145
Normal Sodium
mEq/L
<135
Hyponatremia
mEq/L
3.5-5.0
Normal Potassium
mEq/L
>5.0
Hyperkalemia
mEq/L

Sodium Disorders Management

Hyponatremia (Na+ < 135 mEq/L)

Assessment & Classification

Severe (< 120 mEq/L): Neurological symptoms, seizures
Moderate (120-129 mEq/L): Nausea, headache, confusion
Mild (130-134 mEq/L): Often asymptomatic

Management Algorithm

Severe Hyponatremia:
  • • 3% NaCl 100-150 mL bolus
  • • Target correction: 4-6 mEq/L in 24h
  • • Monitor every 2-4 hours
Moderate Hyponatremia:
  • • Fluid restriction (1-1.5 L/day)
  • • Demeclocycline if SIADH
  • • Vaptans (tolvaptan) if indicated

Hypernatremia (Na+ > 145 mEq/L)

Assessment & Classification

Severe (> 160 mEq/L): Altered mental status, seizures
Moderate (150-160 mEq/L): Thirst, irritability, weakness
Mild (145-150 mEq/L): Often asymptomatic

Management Algorithm

Severe Hypernatremia:
  • • 0.45% NaCl or D5W
  • • Target correction: 10-12 mEq/L in 24h
  • • Monitor every 2-4 hours
Moderate Hypernatremia:
  • • Oral rehydration if possible
  • • Treat underlying cause
  • • Gradual correction over 48-72h

Potassium Disorders Management

Hypokalemia (K+ < 3.5 mEq/L)

Assessment & Classification

Severe (< 2.5 mEq/L): Muscle weakness, arrhythmias
Moderate (2.5-3.0 mEq/L): Fatigue, muscle cramps
Mild (3.0-3.5 mEq/L): Often asymptomatic

Management Algorithm

Severe Hypokalemia:
  • • KCl 20-40 mEq IV over 1-2h
  • • Continuous cardiac monitoring
  • • Target: 3.5-4.0 mEq/L
Moderate Hypokalemia:
  • • KCl 20-40 mEq PO daily
  • • K-sparing diuretics if needed
  • • Treat underlying cause

Hyperkalemia (K+ > 5.0 mEq/L)

Assessment & Classification

Severe (> 6.5 mEq/L): Cardiac arrhythmias, ECG changes
Moderate (5.5-6.5 mEq/L): ECG changes, muscle weakness
Mild (5.0-5.5 mEq/L): Often asymptomatic

Management Algorithm

Severe Hyperkalemia (Emergency):
  • • Calcium gluconate 10% 10mL IV
  • • Insulin 10U + D50 50mL
  • • Albuterol 10-20mg nebulized
  • • Sodium bicarbonate 50mEq
Moderate Hyperkalemia:
  • • Kayexalate 30g PO
  • • Loop diuretics
  • • Dietary K+ restriction

Emergency Protocols

Critical Values Requiring Immediate Action:

  • • Na+ < 120 mEq/L or > 160 mEq/L
  • • K+ < 2.5 mEq/L or > 6.5 mEq/L
  • • Neurological symptoms
  • • Cardiac arrhythmias
  • • ECG changes

Immediate Actions:

  • • Continuous cardiac monitoring
  • • IV access established
  • • Frequent electrolyte monitoring
  • • ICU admission if severe
  • • Consult nephrology/endocrinology

Clinical Pearls & Latest Guidelines

Key Points:

  • • Always correct slowly to avoid osmotic demyelination
  • • Consider underlying cause (SIADH, heart failure, etc.)
  • • Monitor for rebound effects
  • • Use vaptans judiciously in SIADH
  • • Consider renal function in management

2024 Updates:

  • • Tolvaptan approved for SIADH
  • • Patiromer for chronic hyperkalemia
  • • SGLT2 inhibitors affect K+ handling
  • • New guidelines for rapid correction
  • • Emphasis on outpatient management